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991.

Background  

Streptococcus intermedius belongs to the Streptococcus anginosus group. It is part of the normal flora of the human mouth, but it can be etiologically associated with deep-site infections.  相似文献   
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Enthesitis is an inflammatory lesion of the tendon, ligament and capsular insertions into the bone, and it is a fundamental element in the diagnosis of spondyloarthropathies. Sonography is the method of choice for studying periarticular soft tissues because it is capable of detecting both the early (oedema, thickening) and the late alterations (erosions and enthesophytes); it is also an inexpensive, biologically harmless and easily repeatable technique. The aim of this study was to compare the prevalence of quadricipital enthesitis in psoriatic arthritis (PsA) and rheumatoid arthritis (RA) patients, and to document any clinical and echostructural differences in this lesion between the two diseases. The results show that enthesitis is more frequent in PsA patients, more than half of whom are asymptomatic. Knee inflammation was found in the PsA patients with enthesitis regardless of the concomitant presence of joint effusion; none of the RA patients suffered from enthesitis alone. Quadricipital enthesitis is more frequent in male patients. There was no significant correlation between the presence of peripatellar psoriatic lesions and enthesitis. Sonographic examinations of patients with enthesitis revealed that those with RA had dominantly inflammatory lesions, whereas PsA patients also showed major new bone deposition. Received: 24 January 2001 / Accepted: 15 October 2001  相似文献   
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Clinical and Experimental Medicine - Mast cells (MCs) are immune cells derived from myeloid lineage present in all classes of vertebrates and have emerged preceding much time the development of...  相似文献   
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One of the most fascinating aspects of the field of epigenetics is the emerging ability of environmental factors to trigger epigenetic changes in eukaryotic cells, thus contributing to transient or stable, and potentially heritable, changes in gene expression program in the absence of alteration in DNA sequence. Epigenetic response may result in cell adaptation to environmental stimuli or, in some instances, may contribute to generation or progression of different kind of diseases. A paradigmatic case of disease that is accompanied by multiple epigenetic alterations is gastric cancer, among other relevant examples. In turn, Helicobacter pylori (Hp) infection has been associated as a leading cause of gastric cancer. One possible hypothesis is that Hp–gastric cell interaction initiates an epigenetic reprogramming of host cell genome that may favor tumorigenesis. Accordingly, an abundance of experimental evidence indicates that several epigenetic alterations underlie the gastric cancerogenesis process and that these alterations represent one of the major hallmarks of gastric cancer. However, several critical questions remain unanswered: Does Hp directly provoke epigenetic alterations? Which mechanisms underlie these phenomena? Based on currently available data, it is often arduous to discriminate between the epigenetic modifications directly triggered by Hp–gastric cell interaction and those alterations that are mediated by inflammation process or by many other molecular and genetic events occurring during the gastric cancer progression. We will review our present knowledge of epigenetic modifications and alterations proven to occur in host cells as a direct consequence of Hp infection.  相似文献   
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BackgroundPathogenic variants in the dynamin 1 like gene are related to abnormal mitochondrial dynamics and distributions and are associated to variable clinical phenotypes. A few patients harboring the p.Arg403Cys missense variant appears to be different from the classical, more severe phenotypes, showing sudden onset of drug resistant seizures after a previously normal or slightly delayed development.Case reportWe report on a boy with abrupt onset of focal status and coma at the age of 13, initially treated as autoimmune encephalitis, with final diagnosis of de novo missense p.Arg403Cys variant in the DNM1L gene.DiscussionWe compare his clinical, electrophysiological, biochemical, neuroradiological and histopathological picture to the rare cases reported to date and provide diagnostic clues that can help clinicians in differentiate p.Arg403Cys-related phenotype from that of immune-mediated encephalopathies.ConclusionThe clinical picture related to p.Arg403Cys mutations should be considered alongside acquired pathologies in the differential diagnosis of young patients with focal refractory epilepsy and encephalopathy, also occurring during late childhood or adolescence. Prompt genetic testing allows to avoid unnecessary treatments and procedures and to better define the prognosis and management strategies.  相似文献   
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Investigating the innate immune response mediators released in milk has manifold implications, spanning from elucidation of the role played by mammary epithelial cells (MECs) in fighting microbial infections to the discovery of novel diagnostic markers for monitoring udder health in dairy animals. Here, we investigated the mammary gland response following a two-step experimental infection of lactating sheep with the mastitis-associated bacterium Streptococcus uberis. The establishment of infection was confirmed both clinically and by molecular methods, including PCR and fluorescent in situ hybridization of mammary tissues. Proteomic investigation of the milk fat globule (MFG), a complex vesicle released by lactating MECs, enabled detection of enrichment of several proteins involved in inflammation, chemotaxis of immune cells, and antimicrobial defense, including cathelicidins and calprotectin (S100A8/S100A9), in infected animals, suggesting the consistent involvement of MECs in the innate immune response to pathogens. The ability of MECs to produce and release antimicrobial and immune defense proteins was then demonstrated by immunohistochemistry and confocal immunomicroscopy of cathelicidin and the calprotectin subunit S100A9 on mammary tissues. The time course of their release in milk was also assessed by Western immunoblotting along the course of the experimental infection, revealing the rapid increase of these proteins in the MFG fraction in response to the presence of bacteria. Our results support an active role of MECs in the innate immune response of the mammary gland and provide new potential for the development of novel and more sensitive tools for monitoring mastitis in dairy animals.  相似文献   
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